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    Copyright 2006 Google Inc.

    Licensed under the Apache License, Version 2.0 (the "License");
    you may not use this file except in compliance with the License.
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      http://www.apache.org/licenses/LICENSE-2.0

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<!doctype html><html><head>
    <title>ExplorerCanvas Example 1</title>
    <style>
        body {
            background-color:black;
            margin:50px;
            text-align:center;
        }

        canvas {
            border:1px solid #444;
        }
    </style>
<script src="../canvas.vml.js"></script>
<script src="../canvas.js"></script>
<script>
var canvas, ctx;
var particles = [];
var stress = 100;

function Particle() {
    this.x = Math.random() * canvas.width;
    this.y = Math.random() * canvas.height;

    this.xvel = Math.random() * 5 - 2.5;
    this.yvel = Math.random() * 5 - 2.5;
}

Particle.prototype.update = function() {
    this.x += this.xvel;
    this.y += this.yvel;

    this.yvel += 0.1;

    if (this.x > canvas.width || this.x < 0) {
        this.xvel = -this.xvel;
    }

    if (this.y > canvas.height || this.y < 0) {
        this.yvel = -this.yvel;
    }
}

function loop() {
    ctx.lock();

    for(var i = 0; i < stress; i++) {
        particles[i].update();

        if (0) {
            ctx.beginPath();
            ctx.moveTo(particles[i].x, particles[i].y);
            ctx.lineTo(particles[i].x - particles[i].xvel,
                       particles[i].y - particles[i].yvel);
            ctx.closePath();
            ctx.stroke();
        } else {
            ctx.animStrokePath("id" + i,
                               // moveTo()
                               particles[i].x, particles[i].y,
                               // lineTo()
                               [particles[i].x - particles[i].xvel,
                               particles[i].y - particles[i].yvel]);
        }
    }
    ctx.unlock();

    setTimeout(loop, 0);
}

function oncanvasready() {
    canvas = document.getElementById("canvas");
    ctx = canvas.getContext("2d");

    for(var i = 0; i < stress; i++) {
        particles[i] = new Particle();
    }

    ctx.lineWidth = 2;
    ctx.strokeStyle = "white";
    loop();
}
</script>
</head>
<body>
  <h1 id="detected" style="color:white">VMLCanvas.js</h1>
  <canvas id="canvas" width="400" height="300"></canvas>
</body>
</html>
